Fan spots unusual art in The Last of Us developer video.

Naughty Dog has yet to announce a game for the PS4, but a fan has discovered a possible link to a next-gen PlayStation game from the Uncharted developer, according to a report from IGN.

The two figures were spotted in a Naughty Dog video.

A fan captured a still of a Naughty Dog developer video that may contain a glimpse of previously unseen art.

The still, which can be found at the 2:43 mark in the video (embedded below), displays two figures dressed in clothing that does not appear to fit into The Last of Us' present-day universe.

The captured still has led to speculation ranging from new multiplayer components of the upcoming The Last of Us or Uncharted 3: Drake's Deception, to art for an unannounced next-gen title.

The Last of Us is set in a post-apocalyptic world and is exclusive to the PlayStation 3. The game was originally slated for a May 7 release, but was delayed to June 14. At the time, Naughty Dog explained that due to the "massive" nature of the title's story, extra development time was needed to "ensure every detail" was up to the developer's standards.